Proceedings Paper

We studied to develop ITO (Indium Tin Oxide) thin films ablation with a pulsed type KrF excimer ((lambda) equals248 nm) and Nd:YAG laser ((lambda) equals262 and 532 nm) required for the electrode patterning application in flat panel display into small geometry on a large substrate area. The threshold fluence for ablating ITO on glass substrate using KrF excimer laser is about 0.1 J/cm2. In this case, through the optical microscope measurement the surface color of the ablated ITO is changed into dark brown due to increase of surface roughness and transformation of chemical composition by the laser light. And the XPS analysis showed that the relative surface concentration of Sn and In were essentially unchanged (In:Snequals5:1) after irradiating the KrF excimer laser. It has been reported that ripple like structure was by 2nd harmonic Nd:YLF laser (equals523nm). But in case of using 2nd harmonic Nd:YAG laser, in our study, the ablated films have well patterned and the shape is almost clean even though by-product exists in the vicinity of the etched surface region. But the films were damaged at the same laser fluence using 4th harmonic Nd:YAG laser. We will discuss this cause in terms of photon energy and the film thickness, used in this experiment, repetition rate and beam scan speed of each laser.